The crowd praised the spring weather, enjoying the sunshine and gentle breeze as they gathered to attend the ribbon cutting ceremony for a new interactive exhibit at Black Diamond Mines Regional Park.

The dedication, initially postponed due to COVID-19, was, by their own admission, the first time much of the park’s staff had seen each other in person in over a year and their excitement was not hidden. The immersive re-creation of an authentic 20th century coal mine has been several years in the making — so many that those involved cannot recall when the idea first came to them — and the ceremony featured speakers that included Antioch Mayor Pro Tem Monica Wilson as well as representatives who spoke on behalf of Assemblyman Tim Grayson and Congressman Mark DeSaulnier.

The project is the brainchild of former East Bay Regional Park District General Manager Bob Doyle, who retired from the post at the end of 2020, and is estimated to have cost roughly $1.3 million to complete. Much of the funding was achieved through donations from the Regional Parks Foundation and Marathon Petroleum Corp, in addition to a grant from the Wayne and Gladys Valley Foundation, one of the East Bay’s major philanthropic institutions.

Doyle stressed the authenticity of the mine. “In 1977, we went underground with a small group of people and the exhibit is taken from the exact pictures that were taken at that time.” Doyle explained. “It was important to maintain the integrity of the mine work and recognize the hard, hard life that those early Contra Costa workers had here. Pretty amazing.”

East Bay Regional Park District Ward 7 Director Colin Coffey discusses a new mine exhibit at Black Diamond Mines Regional Preserve

Jake Menez/The Press

The first thing guests of the exhibit will notice is the darkness that pervades the mine shaft. Black Diamond was active as a coal mine from 1865 until 1908 and the equipment used by the exhibit is period accurate, meaning the miners lit their way with headlamps made of candles that gave off a dim light. The next thing one might notice is that the simulated shaft, built inside of a real shaft from Black Diamond’s later use as a sand mine, is filled with the sounds of workers speaking and equipment chipping away in search of coal. Colin Coffey, park district board vice president, proudly pointed out that the audio used in the mines features voices that speak in both Welsch and Welsch-accented English, as would have been accurate to the period. The audio was recorded overseas to ensure the realism.

Black Diamond Mines Regional Park plays host to thousands of visitors each year, including an average of about 200 field trips annually. The inclusion of the immersive mine shaft attraction provides just one more way for visitors to have what Coffey calls “an authentic experience, rich in history.” When asked what he looks forward to most about the new exhibit, Coffey responded without hesitation, “The chance to share it with the public and really show more about this piece of Contra Costa’s legacy.”

For more information about Black Diamond Mines and other East Bay regional parks, visit